Making sense of the many iterations of letter mail

On the surface, letter mail seems so simple and straightforward.
You write a letter, put it in an envelope and mail. 
But getting your mail out the door isn’t the issue. It’s about getting response, getting leads or sales or donations. 
And how you structure your letter mail package will have a big impact how many responses you are able to generate.
So what would it take to get the highest possible response?
  • First and foremost, you need an appealing offer with little commitment. This more than anything will drive your response rate. By an appealing offer, I don’t mean your end-product (even if it is appealing). I mean some type of information that will help the prospect with the buying process.
  • Think about how you plan to promote this offer? Will you promote it on the envelope or the letter? Or both?
  • Getting your reader’s attention is critical. How will you highlight the offer? With a headline? With an image?
  • The more response channels, the better. How many different ways will your readers be able to respond? By phone? By mail? By an online landing page?
  • Consider personalization. Will you need or want to personalize your message? Will personalization improve response? If so, at what cost?
Think beyond the simple goal of “getting your mail out the door” – start thinking about how to get them to respond.
What you’ll find is there are many ways to develop your letter mail package to maximize response. Some of these ways cost money or more work on your part – and some may not fit your company image. 
But the fact is there are many different options are available to you – and we’re going to explore those options here.
Part of me wishes this could be simpler. Pick a letter mailer, develop some pricing and sell that same mailer over and over again. To some extent, we do that. We have our default package that works well for many clients and many applications. 
But not all. We get many calls from potential clients who need some variation of our default package. And that’s what this article is about.
My default letter mail package
Before we explore your options, let me start with my default letter mail package.
Here are the specs:
  • #10 window envelope
  • 1-page/1-sided generic letter – not personalized
  • Business reply card – personalized and positioned to show through the envelope window


Understand your Options

There are dozens of alternatives to the default package. 

It’s just a matter of switching out different options for each of the three components – the outer envelope, the letter and the reply device.

The Outer Envelope

Envelope Sizes

First, you have other envelope choices.  A 6×9 envelope is a common size.  There are also a number of smaller size envelopes available but keep in mind you will need to change the sizing of your other components if you take that route.  You may be considering a much larger envelope like 9×12.  This will certainly get your readers’ attention, but you’re going to pay a surcharge in postage.

Odd-sized envelopes and custom-made envelopes are also an option, but these take more time and money to produce because you actually have to manufacture the envelopes.  Also keep in mind to follow postal guidelines or you’ll also pay extra for postage.

Window vs. No Window

But even if you stick with the #10 standard envelope, you have other choices.  You don’t need a window, for example. A closed face envelope will provide a more personalized look and feel.  But you will need to address the envelope (unlike the window).

Envelope Copy & Graphics

You also have a choice of what you put on the envelope.  Generally, you would include the company logo and return address in the upper left corner.  If your business name does not explain what you, I often recommend adding a tag line to provide some clarity.

You could use so-called “teaser copy” to entice more people to open the envelope.  Teaser copy has been shown to be effective (I often recommend it), but not everyone likes the look of teaser copy.


You also have a choice of postage – both the rate (first class vs. standard class) and the method of affixing postage.  Postage can appear as a printed indicia so it’s actually on the piece before it’s printed. But for a slight increase in costs, you could have actual stamps affixed to the envelope.

The Letter    

Personalized vs. Generic

The letter described in my default format was a generic letter – not personalized.  But many people want a personalized letter.

What do we mean by personalized letter?  Generally, it’s a letter with the name and address of the contact in the address block at the top followed by a personalized salutation (Dear John). That would be the minimum.

But sometimes you want to personalize the content as well – to insert references that help to convey a more one-to-one communication. For example, you might insert John’s name at some point in the letter.   (John, we’ve appreciated your support in the past)

Or you might insert John’s company (we know how important this is to ABC Company).

Fundraising letters do a lot of letter personalization because it allows them to reference past donations (thank you for recent donation of $100).   And then they structure their “ask” for another donation accordingly. (I hope we count you again with another gift of $100 or more.)

As you can imagine, personalized letters cost more than generic letters because they need to be printed one at a time.  A generic letter is printed in volume.  Personalized letters are often printed as shells in volume and then personalized as a second step.  The one exception would be a personalized letter on a digital press where it’s all done at one time – but that is usually reserved for smaller press runs.

A lower cost option for personalizing a letter is to pre-print the letter, but then insert the address block and/or salutation with lower cost inkjet addressing.  This is a little tricky because you need to match the inkjet address text (type face and type size) with the letter text to make it seem like one run.

One Sided vs. Two Sided

Another option for the letter is the length.  Many letters – particularly for lead generation – get by with just one page of text.  You can’t say too much with one page, but that’s okay – you don’t want to say too much with some lead generation efforts. 

But if your letter requires a longer explanation or you feel the reader needs more information, you may need to go to a second page – either the back of the first page or a second piece of paper. 

Here’s what you shouldn’t do:  try to squeeze a two-page letter into one page.  You have a lot to say but you don’t want to go to two pages because of cost or because you believe people won’t read two pages.  Trust me:  more people will read your letter if it’s presented properly with generous spacing.

Headline vs. No Headline

When we think of a traditional letter, we don’t think of headlines.  We think of an address block, a salutation and straight forward letter.  That’s what we all expect from a letter from a friend (boy, that’s nostalgic), from the bank or from your lawyer.  Business mail. Nothing fancy. Just a simple message.

But we’ve learned over the years is that letters with headlines (and even some graphics) can produce higher response than letters with no headlines. 

People read headlines before they read letter text (and even if they don’t read the text), so this makes sense.  It may take away from the look and feel you’re expecting from a letter, but it will get your message across to more readers which should lead to higher response.


The Reply Card

Business Reply vs. Courtesy Reply

In my default package, I list the reply card as a business reply card – meaning a card that can be returned to you at no cost to the respondent.  This is what you want ideally – especially for consumer mail where response hesitation may come from the fact that postage stamps are not readily available. 

This is less of concern for B2B marketers because businesses often have a built-in process for sending out daily mail.

To have a business reply card, you need to set up a business reply account with post office.  It’s a few hundred dollars for an annual permit and it could take a week or so to set up.  After that, you only pay for replies that come to you (around $1 per piece).

If you don’t want to set up a business reply account, you can change your reply card to be a “courtesy” reply card.  This means the respondent pays the postage (they would have to place a stamp on the reply card).  As I said, this works better in B2B applications.

Reply Cards vs. Reply Slips (with Reply Envelopes)

A reply card works well in many applications, but there are some situations that require a reply slip and reply envelope.

If you are expecting responses to come in the form of checks and/or credit card information, you need to use an envelope.  Fundraisers typically have a donation form along with a courtesy reply envelope.  They use “courtesy” envelopes telling their donors that their donations can be better used for the cause than for paying for reply postage.

But it’s not just financial transactions.  Sometimes, you are asking respondents to provide some personal information with their response – at least personal enough to warrant some privacy. 

We use reply envelopes for survey mailings in which the completed survey is returned in a reply envelope. 

Of course, a reply slip and reply envelope will cost more than just a reply card so that’s a consideration.

Expanded Reply Cards or Reply Slips

Occasionally, we design two-panel reply cards or reply slips.  These are often folded and perforated so the two panels can be separated.  One panel is returned for response; the other panel stays with the recipient to reinforce the message.

If we are using a large envelope, such as a 6×9, we might design a large reply card of which only a portion is the mail-back reply card.

No Reply Device

Of course, some clients don’t want to deal with reply mail and choose to skip this piece entirely.

They want phone calls – and phone calls only. 

Don’t we all.  Phone calls are great leads (much better than reply mail leads) because you have them on the phone. 

But be warned, when you only provide a phone call option for a free quote or to learn more, you will get fewer leads.  That’s just a fact.

For all of our direct mail campaigns, we recommend multiple response channels – meaning reply mail, the phone and a dedicated landing page.

A landing page (not your home page) will provide more responses from those who may be interested in what you offer but are not ready to hop the phone to speak to a sales rep. 

The Role of Personalization

When you look at the overall cost of a direct mail campaign, the two biggest factors are postage and printing.  

There’s nothing you can do with postage other than take advantage of every pre-sorting and pre-barcoding discount available. 

Printing costs are determined obviously by how much printing is involved.  More specifically, how many components are in the mailing package and how many mailing packages will be produced. 

But personalization can also play a big role. 

Consider a mailing that has a personalized envelope, a personalized letter and a personalized reply card.  Each of these three pieces will need to be personally addressed separately and then they will need to matched for inserting and double-checked to make sure they go into the right envelope.

This is three-way personalization and it comes with signification costs.  Why?  Because in addition to printing, each piece needs to be separately personalized.

But you don’t need to personalize everything. 

As long as an address appears on the outer envelope (or through a window), your mail will be delivered – and that’s half the battle. If you use a window, you can place your address on either the letter or the reply card and have it show through a window – giving you two-way personalization for the price of one.

Extensive personalization may very well improve your response rate. But there’s no guarantee.  The only guarantee is that it will increase your costs.


Letter mail is a popular direct mail format – perhaps the most popular format for seasoned direct marketers.  And while we may have our preferences, there is no such thing as an established letter mail package. 

What works for you may not work for the next person. 

If you’d like to discuss your own letter mail package, call us to schedule a free strategy session. 


A Quick Word About Us

We create lead generation campaigns using Direct Marketing or Digital Marketing – and very often a combination of the two, which we describe as Digital Direct Mail.

Our campaigns include both Outbound Marketing (direct mail, cold email, phone) and Inbound Marketing (SEO, PPC, Local Search) as well as Lead Nurturing funnel activities.

If lead generation is in your plans, we invite you to download our FREE Guide, The Lead Generation Blueprint. Or click here to schedule an Exploratory Phone Call.

About Bob McCarthy

Bob McCarthy is a direct response consultant and copywriter with a focus on direct mail, email and digital marketing. Bob works with B2B, B2C and Non-Profit clients. You can download his free ebook, "Making Snail Mail Work: 13 Lessons in Direct Mail Strategy."